What has to be remembered here is that the unit will only flow what the
engine is capable of pumping. John's figures are likely correct as the
I have a similar set up, but big isn't always better! The flow will be
limited by heads, cam, bore & stroke, etc. In this area velocity is
king! I have been told that a good set of production heads can be ruined
by improper porting.
I remember well in the old days drag racing, people would remove the
velocity controls in the secondaries on carburetors or install
carburetors that were too large for the engine. The result was a
stumbling off the line and loss in the low end performance.
Tom, Redding CA, #216 D/CC - Its raining and in the 50's here.
> I am afraid this is not nearly as much as you think as each cylinder
> only sees 1 bore so it is not all that much air flow as you might think.
> With a carb or any other plenum manifold all the cylinders see all the
> airflow...and there are always 2 on some part of an intake stroke with a
> John Beckett wrote:
> > Dave
> > Can get you close. A throttle opening of 2.25" had a general flow rating of
> > 446 cfm. Times 8 = 3568 cfm. Little bigger than your standard Holley carb.
> > There may also be other factors (manifolds shape, etc.) that diminish this
> > cfm number some what, but it's still up there.
> > John Beckett, LSR #79
> > ----- Original Message -----
> > From: "David Haller" <firstname.lastname@example.org>
> > To: "land speed" <email@example.com>
> > Sent: Tuesday, January 18, 2000 9:05 PM
> > > List,
> > > Can somebody out there tell me how to figure cfm on 8 2 5/16 butterflys on
> > a
> > > hilborn injections system?
> > > Thanks,
> > > Dave Haller #93
> > >